Tesla's chief financial officer, Deepak Ahuja, said of the commitment to begin repayment, "We are delivering on the milestones, what we've committed to. Once we are delivering customer cars, then that signifies completion of the project."

Tesla predicts it will deliver some 5,000 Model S sedans by year end, including the first 1,000 built as "signature Series" models. The Signature Series models come loaded and including the automaker's largest 85 kWh battery pack, which will reportedly deliver a highway range of 250 miles at 70 mph.

To reduce the cost of the Model S, Tesla will offer future variants with the option of a 60 kWh battery pack or a 40 kWh battery pack, which will reduce the sedan's range accordingly/

Of Tesla’s commitment to begin repaying the loans by year end, Department of Energy spokesman Damien LaVera said, “We are pleased that Tesla continues to make progress and look forward to working with them as clean, electric vehicles play an important role in our energy future.”